25 December 2011

A gift

Today, many of you are enjoying gifts from other people. I want to talk about one my favourite natural gifts.

For me, the best gifts are the unexpected ones; the ones you didn’t have to get. A present from someone you don’t know all that well, for instance, can be very memorable.

There are many things in nature that are beautiful. But because they lack that unexpected quality, they don’t rank as my favourite natural gifts. Rainbows, for instance. Given water droplets, some light, and the laws of optics, rainbows are inevitable. You can’t not have rainbows. Any planet in the cosmos with water and light will have rainbows.

Yet the sun is so much further away than the moon that it almost exactly compensates for the difference in size. There is no reason that our star and our satellite should match up this way. Either could be a different size or different distance away. There are probably only a small number of planets in the galaxy where you would get this view from the ground.

And that makes this possible:

The best gifts are the ones you didn’t have to get. And this coincidence makes for what may be the best gift from our planet.